Add comments to network permission declaration am: 9108bc59f6

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/modules/NetworkStack/+/17940023

Change-Id: I2a474ac4cd5f4246c2b1615b420e5ffd874d1296
Ignore-AOSP-First: this is an automerge
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>